Since Nuance no longer actively hosts the installer for version 12 on their main product page, you have two primary options:
If you bought PaperPort 12 from Nuance’s e-store, check your email for a download link that was originally http://www.nuance.com/activations/pp12/. Most such links redirect now, but you can contact Kofax customer support with your serial number—they often provide a fresh download link. download and install nuance paperport 12 link
For educational or non-commercial re-installation, some academic software archives host the original ISO. Always verify MD5/SHA checksums against known good values if possible. Select features:
Warning: Do NOT use "keygen" or "crack" sites promising a free download and install Nuance PaperPort 12 link. These are vectors for ransomware and keyloggers. Click Install